Mesoscale Analysis of Stress Distribution along ITZs in Recycled Concrete with Variously Shaped Aggregates under Uniaxial Compression

Recycled aggregate concrete (RAC) has attracted tremendous attention from engineering practice and academic research throughout the world as an effective way to resolve the problems caused by the construction and demolition waste. It is generally accepted that RAC consists of five phases [(1) natural aggregate, (2) old interfacial transition zone (ITZ), (3) old hydrated cement paste, (4) new interfacial transition zone, and (5) new hydrated cement paste], among which the interfacial transition zones are of great significance to the behavior of RAC, due to their characterizations as the weakest links in the concrete mixture. It has been recognized that the shape of aggregates plays an important role in the mechanical behavior of concrete. However, there is very limited information about the shape effect of aggregates on the behavior of the ITZs in RAC. A mesoscale model of RAC is employed in the research reported in this paper to investigate the mechanical behavior of the ITZs under uniaxial compression with differently shaped aggregates. Large stress concentration factors (SCF) have been found at the morphological transitions of the aggregate. A comparison between the distributions of SCF along the ITZs indicates that the shape of aggregates has a more pronounced influence on the stress distribution along the old ITZ than that along the new ITZ, which may be due to the old hydrated cement paste attenuating the shape effect of aggregates on the new ITZ. A quadratic polynomial equation can be curve-fitted to characterize the relationship between the maximum SCF along the ITZs and the fractal dimensions of aggregates.

• Record URL:
  • https://doi.org/10.1061/(ASCE)MT.1943-5533.0001280
• Record URL:
  • http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29MT.1943-5533.0001280
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/08991561
• Supplemental Notes:
  • © 2015 American Society of Civil Engineers.
• Authors:
  • Liu, Zhen
  • Peng, Hui
  • Cai, C S
• Publication Date: 2015-11

Language

• English

Media Info

• Media Type: Web
• Features: References;
• Pagination: 04015024
• Serial:
  • Journal of Materials in Civil Engineering
  • Volume: 27
  • Issue Number: 11
  • Publisher: American Society of Civil Engineers
  • ISSN: 0899-1561
  • EISSN: 1943-5533
  • Serial URL: http://ascelibrary.org/journal/jmcee7

Subject/Index Terms

• TRT Terms: Admixtures; Aggregates; Cement paste; Compression; Mechanics; Recycled materials; Uniaxial stress
• Uncontrolled Terms: Interfacial transition zone
• Subject Areas: Highways; Materials; I32: Concrete;

Filing Info

• Accession Number: 01558564
• Record Type: Publication
• Files: TRIS, ASCE
• Created Date: Mar 31 2015 9:06AM